The present invention relates to a liquid ejecting head, a liquid ejecting apparatus, using the liquid ejecting head and a recovery method for the liquid ejecting apparatus, wherein desired liquid is ejected by generation of the bubble by applying thermal energy to the liquid.
More particularly, it relates to a liquid ejecting head having a movable member movable by generation of a bubble, and a head cartridge using the liquid ejecting head, and liquid ejecting device using the same. It further relates to a liquid ejecting method and recording method for ejection the liquid by moving the movable member using the generation of the bubble.
The present invention is applicable to equipment such as a printer, a copying machine, a facsimile machine having a communication system, a word processor having a printer portion or the like, and an industrial recording device combined with various processing device or processing devices, in which the recording is effected on a recording material such as paper, thread, fiber, textile, leather, metal, plastic resin material, glass, wood, ceramic and so on.
In this specification, xe2x80x9crecordingxe2x80x9d means not only forming an image of letter, figure or the like having specific meanings, but also includes forming an image of a pattern not having a specific meaning.
An ink jet recording method of so-called bubble jet type is known in which an instantaneous state change resulting in an instantaneous volume change (bubble generation) is caused by application of energy such as heat to the ink, so as to eject the ink through the ejection outlet by the force resulted from the state change by which the ink is ejected to and deposited on the recording material to form an image formation. As disclosed in U.S. Pat. No. 4,723,129, a recording device using the bubble jet recording method comprises an ejection outlet for ejecting the ink, an ink flow path in fluid communication with the ejection outlet, and an electrothermal transducer as energy generating means disposed in the ink flow path.
With such a recording method is advantageous in that, a high quality image, can be recorded at high speed and with low noise, and a plurality of such ejection outlets can be posited at high density, and therefore, small size recording apparatus capable of providing a high resolution can be provided, and color images can be easily formed. Therefore, the bubble jet recording method is now widely used in printers, copying machines, facsimile machines or another office equipment, and for industrial systems such as textile printing device or the like.
With the increase of the wide needs for the bubble jet technique, various demands are imposed thereon, recently.
For example, an improvement in energy use efficiency is demanded. To meet the demand, the optimization of the heat generating element such as adjustment of the thickness of the protecting film is investigated. This method is effective in that a propagation efficiency of the generated heat to the liquid is improved.
In order to provide high image quality images, driving conditions have been proposed by which the ink ejection speed is increased, and/or the bubble generation is stabilized to accomplish better ink ejection. As another example, from the standpoint of increasing the recording speed, flow passage configuration improvements have been proposed by which the speed of liquid filling (refilling) into the liquid flow path is increased.
Japanese Laid Open Patent Application No. SHO-63-199972 or the like discloses a flow passage structure as shown in FIGS. 45, (a), (b). The invention of the flow passage structure and the head manufacturing method disclosed in the publication, is particularly directed to the backward liquid generated in accordance with generation of a bubble (the pressure propagated away from the ejection outlet namely toward the liquid chamber 12). The back wave is known as energy loss since it is not propagated toward the ejection direction.
FIGS. 61, (a) and (b) disclose a valve 10 spaced from a generating region of the bubble generated by the heat generating element 2 in a direction away from the ejection outlet 11.
In FIG. 61, (b), this valve 10, is so manufactured from a plate that it has an initial position where it looks as if it stick on the ceiling of the flow path 3, and is deflected downward into the flow path 3 upon the generation of the bubble. Thus, the energy loss is suppressed by controlling a part of the backward wave by the valve 10.
However, with this structure, if the consideration is made as-to the time when the bubble is generated in the flow path 3 having the liquid to be ejected, the suppression of a part of the backward wave by the valve 10 is not desirable.
The backward wave per se is not contributable to the ejection. At the time when the backward wave is generated inside the flow path 3, the pressure directly contributable to the ejection has already make the liquid ejectable from the flow path 3, as shown in FIG. 61, (a). Therefore, even if the backward wave is suppressed, the ejection is not significantly influenced, much less even if a part thereof is suppressed.
On the other hand, in the bubble jet recording method, the heating is repeated with the heat generating element contacted with the ink, and therefore, a burnt material is deposited on the surface of the heat generating element due to burnt deposit of the ink. However, the amount of the deposition may be large depending on the materials of the ink. If this occurs, the ink ejection becomes unstable. Even when it the liquid to be ejected is easily deteriorated by the heat, or is not sufficiently formed into a bubble, the liquid is desirably ejected without deterioration of the liquid.
From this standpoint, Japanese Laid Open Patent Application No. SHO-61-69467, Japanese Laid Open Patent Application No. SHO-55-81172 and U.S. Pat. No. 4,480,259 disclose that different liquids are used for the liquid generating the bubble by the heat (bubble generating liquid) and for the liquid to be ejected (ejection liquid). In these publications, the ink as the ejection liquid and the bubble generation liquid are completely separated by a flexible film of silicone rubber or the like so as to prevent direct contact of the ejection liquid to the heat generating element while propagating the pressure resulting from the bubble generation of the bubble generation liquid to the ejection liquid by the deformation of the flexible film. The prevention of the deposition of the material on the surface of the heat generating element and the increase of the selection latitude of the ejection liquid are accomplished, by such a structure.
However, with this structure in which the ejection liquid and the bubble generation liquid are completely separated, the pressure by the bubble generation is propagated to the ejection liquid through the expansion-contraction deformation of the flexible film, and therefore, the pressure is absorbed by the flexible film to quite a high degree. In addition, the deformation of the flexible film is not so large, and therefore, the energy use efficiency and the ejection force are deteriorated although the some effect is provided by the provision between the ejection liquid and the bubble generation liquid.
Accordingly, it is a principal object of the present invention to provide a liquid ejecting method and device provided with ejection power refreshing means, wherein an ejection efficiency, is high, and ejection power is large, and still satisfactory ejection is possible even after long term non-use condition.
It is another object of the present invention to provide a novel and effective liquid ejection.
It is a further object of the present invention to provide a liquid ejecting method, and liquid ejecting head or the like wherein the ejection efficiency, and the ejection power are high, and the heat accumulation of the liquid on the heat generating element can be significantly reduced, and the residual bubble on the heat generating element can be reduced.
It is a further object of the present invention to provide a liquid ejecting head or the like, wherein inertia force in the opposite direction from the liquid supply direction due to the backward wave is suppressed, and simultaneously, the meniscus retraction amount is reduced by the valve function of the movable member, by which the refilling frequency is increased, and the printing speed is improved.
It is a further object of the present invention to provide a liquid ejecting head and so on wherein deposition of residual material on the heat generating element is reduced, and the range of the usable liquid is widened, and in addition, the ejection efficiency and the ejection force are significantly increased.
It is a further object of the present invention to provide a liquid ejecting method, a liquid ejecting head and so on, wherein the choice of the liquid to be ejected is made greater.
According to an aspect of the present invention, there is provided a liquid ejection head comprising: an ejection outlet for ejecting liquid; a bubble generating region for generating a bubble; a movable member disposed faced to the bubble generating region and movable between a first position and a second position which is farther form the bubble generating region than the first position; a liquid supply passage for supplying the liquid to the bubble generating region from upstream of the bubble generating region; an opening, in fluid communication with the supply passage, for discharging the liquid.
According to another aspect of the present invention, there is provided a liquid ejection head comprising: an ejection outlet for ejecting liquid; a liquid path having a heat generating element for generating a bubble in the liquid by application of heat to the liquid, and a supply passage for supplying the liquid to the heat generating element from upstream side thereof; a movable member, disposed faced to the heat generating element and having a free end adjacent the ejection outlet, for directing a pressure produced by generation of the bubble, toward the ejection outlet, on the basis of the pressure produced by the generation of the bubble; and an opening, in fluid communication with the supply passage, for discharging the liquid.
According to a further aspect of the present invention, there is provided a liquid ejection head comprising: an ejection outlet for ejecting liquid; a heat generating element for generating a bubble in the liquid by application of heat to the liquid; a movable member, disposed faced to the heat generating element and having a free end adjacent the ejection outlet, for directing a pressure produced by generation of the bubble, toward the ejection outlet; a supply passage for supplying the liquid to the heat generating element from an upstream thereof along a surface of the movable member adjacent the heat generating element; an opening, in fluid communication with the supply passage, for discharging the liquid.
According to a further aspect of the present invention, there is provided a liquid ejection head comprising: a first liquid flow path in fluid communication with an ejection outlet; a second liquid flow path having bubble generation region for generating the bubble in the liquid by applying heat to the liquid; a movable member, disposed between the first liquid flow path and the bubble generating region and having a free end adjacent the ejection outlet, for directing a pressure produced by generation of the bubble, toward the ejection outlet of the first liquid flow path, by movement of the free end into the first liquid flow path on the basis of pressure produced by generation of the bubble the bubble generating region; an opening, in fluid communication with the supply passage, for discharging the liquid.
According to a further aspect of the present invention, there is provided a liquid ejection head comprising: a plurality of ejection outlet for ejecting liquid; a plurality of grooves for constituting a plurality of first liquid flow paths in direct fluid communication with associated ones of the ejection outlets; a recess for constituting a first common liquid chamber for supplying the liquid to the first liquid flow paths; wherein the grooves and the recess are formed in a grooved member; an element substrate having a plurality of heat generating elements for generating the bubble in the liquid by applying heat to the liquid; and a partition wall disposed between the grooved member and the element substrate and forming a part of walls of second liquid flow paths corresponding to the heat generating elements, and a movable member movable into the first liquid flow paths by pressure produced by the generation of the bubble, the movable member being faced to the heat generating element; and an opening, in fluid communication with the supply passage, for discharging the liquid.
According to a further aspect of the present invention, there is provided a liquid ejection apparatus comprising: a liquid ejecting head for ejecting liquid by generation of bubble, including an ejection outlet for ejecting the liquid; a bubble generation region for generating the bubble in the liquid; a movable member disposed faced to the bubble generation region and displaceable between a first position and a second position further from the bubble generation region than the first position; wherein the movable member moves from the first position to the second position by pressure produced by the generation of the bubble to permit expansion of the bubble more in a downstream side closer to the ejection outlet than in an upstream side; and means for discharging the liquid through the ejection outlet.
According to a further aspect of the present invention, there is provided a liquid ejection apparatus comprising: a liquid ejection head including an ejection outlet for ejecting liquid; a liquid path having a heat generating element for generating a bubble in the liquid-by application of heat to the liquid, and a supply passage for supplying the liquid to the heat generating element from upstream side thereof; a movable member, disposed faced to the heat generating element and having a free end adjacent the ejection outlet, for directing a pressure produced by generation of the bubble, toward the ejection outlet, on the basis of the pressure produced by the generation of the bubble; and means for discharging the liquid through the ejection outlet.
According to a further aspect of the present invention, there is provided a liquid ejection apparatus comprising: a liquid ejection head including an ejection outlet for ejecting liquid; an ejection outlet for ejecting liquid; a heat generating element for generating a bubble in the liquid by application of heat to the liquid; a movable member, disposed faced to the heat generating element and having a free end adjacent the ejection outlet, for directing a pressure produced by generation of the bubble, toward the ejection outlet; and a supply passage for supplying the liquid to the heat generating element from an upstream thereof along a surface of the movable member adjacent the heat generating element; means for discharging the liquid through the ejection outlet.
According to a further aspect of the present invention, there is provided a liquid ejection apparatus comprising: a liquid ejection head including a first liquid flow path in fluid communication with an ejection outlet; a second liquid flow path having bubble generation region for generating the bubble in the liquid by applying heat to the liquid; and a movable member, disposed between the first liquid flow path and the bubble generating region and having a free end adjacent the ejection outlet, for directing a pressure produced by generation of the bubble, toward the ejection outlet of the first liquid flow path, by movement of the free end into the first liquid flow path on the basis of pressure produced by generation of the bubble the bubble generating region; and means for discharging the liquid through the ejection outlet.
According to a further aspect of the present invention, there is provided a liquid ejection apparatus comprising: a liquid ejection head including a plurality of ejection outlet for ejecting liquid; a plurality of grooves for constituting a plurality of first liquid flow paths in direct fluid communication with associated ones of the ejection outlets; a recess for constituting a first common liquid chamber for supplying the liquid to the first liquid flow paths; wherein the grooves and the recess are formed in a grooved member; an element substrate having a plurality of heat generating elements for generating the bubble in the liquid by applying heat to the liquid; and a partition wall disposed between the grooved member and the element substrate and forming a part of walls of second liquid flow paths corresponding to the heat generating elements, and a movable member movable into the first liquid flow paths by pressure produced by the generation of the bubble, the movable member being faced to the heat generating element; and means for discharging the liquid through the ejection outlet.
According to a further aspect of the present invention, there is provided a recovering method for a liquid ejection apparatus comprising: a liquid ejecting head for ejecting liquid by generation of bubble, including an ejection outlet for ejecting the liquid; a bubble generation region for generating the bubble in the liquid; a movable member disposed faced to the bubble generation region and displaceable between a first position and a second position further from the bubble generation region than the first position; wherein the movable member moves from the first position to the second position by pressure produced by the generation of the bubble to permit expansion of the bubble more in a downstream side closer to the ejection outlet than in an upstream side; the improvement residing in that the liquid is discharged through the ejection outlet to recover ejection power of the liquid ejecting head.
According to a further aspect of the present invention, there is provided a recovering method for a liquid ejection apparatus comprising: a liquid ejecting head for ejecting liquid by generation of bubble, including an ejection outlet for ejecting the liquid; a bubble generation region for generating the bubble in the liquid; a movable member disposed faced to the bubble generation region and displaceable between a first position and a second position further from the bubble generation region than the first position; wherein the movable member moves from the first position to the second position by pressure produced by the generation of the bubble to permit expansion of the bubble more in a downstream side closer to the ejection outlet than in an upstream side; and an opening, in fluid communication with the supply passage, for discharging the liquid; the improvement residing in that the liquid is discharged through the ejection outlet and/or the opening to recover ejection power of the liquid ejecting head.
According to a further aspect of the present invention, there is provided a recovering method for a liquid ejection apparatus comprising: a liquid ejection head including an ejection outlet for ejecting liquid; a liquid path having a heat generating element for generating a bubble in the liquid by application of heat to the liquid, and a supply passage for supplying the liquid to the heat generating element from upstream side thereof; a movable member, disposed faced to the heat generating element and having a free end adjacent the ejection outlet, for directing a pressure produced by generation of the bubble, toward the ejection outlet, on the basis of the pressure produced by the generation of the bubble; the improvement residing in that the liquid is discharged through the ejection outlet to recover ejection power of the liquid ejecting head.
According to a further aspect of the present invention, there is provided a recovering method for a liquid ejection apparatus comprising: a liquid ejection head including an ejection outlet for ejecting liquid; a liquid path having a heat generating element for generating a bubble in the liquid by application of heat to the liquid, and a supply passage for supplying the liquid to the heat generating element from upstream side thereof; a movable member, disposed faced to the heat generating element and having a free end adjacent the ejection outlet, for directing a pressure produced by generation of the bubble, toward the ejection outlet, on the basis of the pressure produced by the generation of the bubble; and an opening, in fluid communication with the supply passage, for discharging the liquid; the improvement residing in that the liquid is discharged through the ejection outlet and/or the opening to recover ejection power of the liquid ejecting head.
According to a further aspect of the present invention, there is provided a recovering method for a liquid ejection apparatus comprising: a liquid ejection head including an ejection outlet for ejecting liquid; an ejection outlet for ejecting liquid; a heat generating element for generating a bubble in the liquid by application of heat to the liquid; a movable member, disposed faced to the heat generating element and having a free end adjacent the ejection outlet, for directing a pressure produced by generation of the bubble, toward the ejection outlet; and a supply passage for supplying the liquid to the heat generating element from an upstream thereof along a surface of the movable member adjacent the heat generating element; the improvement residing in that the liquid is discharged through the ejection outlet to recover ejection power of the liquid ejecting head.
According to a further aspect of the present invention, there is provided a recovering method for a liquid ejection apparatus comprising: a liquid ejection head including an ejection outlet for ejecting liquid; an ejection outlet for ejecting liquid; a heat generating element for generating a bubble in the liquid by application of heat to the liquid; a movable member, disposed faced to the heat generating element and having a free end adjacent the ejection outlet, for directing a pressure produced by generation of the bubble, toward the ejection outlet; and a supply passage for supplying the liquid to the heat generating element from an upstream thereof along a surface of the movable member adjacent the heat generating element; and an opening, in fluid communication with the supply passage, for discharging the liquid; the improvement residing in that the liquid is discharged through the ejection outlet and/or the opening to recover ejection plower of the liquid ejecting head.
According to a further aspect of the present invention, there is provided a recovery method for a liquid ejection apparatus comprising: a liquid ejection head including a first liquid flow path in fluid communication with an ejection outlet; a second liquid flow path having bubble generation region for generating the bubble in the liquid by applying heat to the liquid; and a movable member, disposed between the first liquid flow path and the bubble generating region and having a free end adjacent the ejection outlet, for directing a pressure produced by generation of the bubble, toward the ejection outlet of the first liquid flow path, by movement of the free end into the first liquid flow path on the basis of pressure produced by generation of the bubble the bubble generating region; the improvement residing in that the liquid is discharged through the ejection outlet to recover ejection power of the liquid ejecting head.
According to a further aspect of the present invention, there is provided a recovery method for a liquid ejection apparatus comprising: a liquid ejection head including a first liquid flow path in fluid communication with an ejection outlet; a second liquid flow path having bubble generation region for generating the bubble in the liquid by applying heat to the liquid; and a movable member, disposed between the first liquid flow path and the bubble generating region and having a free end adjacent the ejection outlet, for directing a pressure produced by generation of the bubble, toward the ejection outlet of the first liquid flow path, by movement of the free end into the first liquid flow path on the basis of pressure produced by generation of the bubble the bubble generating region; and an opening, in fluid communication with the supply passage, for discharging the liquid; the improvement residing in that the liquid is discharged through the ejection outlet and/or the opening to recover ejection power of the liquid ejecting head.
According to a further aspect of the present invention, there is provided a recovery method for a liquid ejection apparatus comprising: a liquid ejection head including a plurality of ejection outlet for ejecting liquid; a plurality of grooves for constituting a plurality of first liquid flow paths in direct fluid communication with associated ones of the ejection outlets; a recess for constituting a first common liquid chamber for supplying the liquid to the first liquid flow paths; wherein the grooves and the recess are formed in a grooved member; an element substrate having a plurality of heat generating elements for generating the bubble in the liquid by applying heat to the liquid; and a partition wall disposed between the grooved member and the element substrate and forming a part of walls of second liquid flow paths corresponding to the heat generating elements, and a movable member movable into the first liquid flow paths by pressure produced by the generation of the bubble, the movable member being faced to the heat generating element; the improvement residing in that the liquid is discharged through the ejection outlet to recover ejection power of the liquid ejecting head.
According to a further aspect of the present invention, there is provided a recovering method for a liquid ejection apparatus comprising: a liquid ejection head including a plurality of ejection outlet for ejecting liquid; a plurality of grooves for constituting a plurality of first liquid flow paths in direct fluid communication with associated ones of the ejection outlets; a recess for constituting a first common liquid chamber for supplying the liquid to the first liquid flow paths; wherein the grooves and the recess are formed in a grooved member; an element substrate having a plurality of heat generating elements for generating the bubble in the liquid by applying heat to the liquid; and a partition wall disposed between the grooved member and the element substrate and forming a part of walls of second liquid flow paths corresponding to the heat generating elements, and a movable member movable into the first liquid flow paths by pressure produced by the generation of the bubble, the movable member being faced to the heat generating element; and an opening, in fluid communication with the supply passage, for discharging the liquid; the improvement residing in that the liquid is discharged through the ejection outlet and/or the opening to recover ejection power of the liquid ejecting head.
The liquid in the liquid path in single liquid flow path structure is sucked out, or the liquids in the paths in the two-flow-path structure are simultaneously sucked out, through the ejection outlets, or they are pressurized, so that the viscosity-increased ink, foreign matter or the like which is liable to be deposited at the ejection outlet portion after long non-use period, can be efficiently removed, and the precipitated bubble in the liquid in the first liquid flow path can be efficiently removed. According to the present invention, when the ejection liquid and bubble generation liquid are used, the mixture of the two liquids can be avoided even if the recording head or the like is kept intact for quite a long term.
With the structure of the bubble generating portion side liquid flow path having a path open to the outside, the liquids in the two paths isolated by the movable member are efficiently discharged by the suction means or pressing means. With this structure, the number, amount, order, and the timing of the discharge for the liquids in both of the flow paths are selectable.
In addition, by increasing the flow rate by opening the flow rate adjusting means upon the suction operation through the ejection outlet, the removal of the viscosity-increased ink or the like can be further efficient.
Adjustment of the suction amount of each liquid using the static head difference between the liquid, or suction under the condition that the flow resistances of the liquids are the same, are effective to increase the efficiency of the removal of the viscosity-increased ink or the like. Suction while the movable member takes the position in the first liquid flow path, is very effective.
When the liquid ejecting method, and the head using the movable member, the ejection efficiency can be increased. For example, in the most desirable type of the present invention, the ejection efficiency is increased even to twice the conventional one.
The ejection failure can be avoided even after long term non-use under low temperature and low humidity conditions, and even if the ejection failure occurs, the normal state is restored by small scale refreshing process such as preliminary ejection or suction recovery. The said refreshing process will be described in detail hereinafter.
According to the present invention, the time required for the recovery can be reduced, and the loss of the liquid by the recovery operation is reduced, so that the running cost can be reduced.
According to an aspect of the present invention wherein the refilling property is improved, the responsivity, stabilized growth of the bubble, and the stabilization of the droplet are accomplished under the condition of the continuous ejection, so that the high speed recording and high image quality recording are accomplished by the high speed liquid ejection.
These and other objects, features and advantages of the present invention will become more apparent upon a consideration of the following description of the preferred embodiments of the present invention taken in conjunction with the accompanying drawings.